Rivet and mandrel assembly



March 29, 1960 J. F. HAMLIN ETA!- 2,930,503

RIVET AND MANDREL ASSEMBLY Original Filed Feb. 1, 1956 'IIIIIIIIIIIINVEN 1 CR5 JERRY F. HAMLIN LOUIS NEWMAN BUCKHORN, CHEATHAM 8 BLOREATTORNEYS Unite rates RIVET AND MANDREL ASSEMBLY Original applicationFebruary 1, 1956, Serial No. 562,793. gzigided and this applicationApril 21, 1958, Serial No.

2 Claims. (Cl. 218-28) The present invention relates to a rivet andmandrel assembly for riveting guns for blind rivets, and is particularlyadapted for employment in a gun which is an improvement on the structureshown in Hamlin Patent No. 2,570,801, issued October 9, 1951. Moreparticularly the invention concerns a rivet and mandrel assembly forriveting gun of the above character which assembly facilitates easyhandling and loading of the rivets. This application is a division ofour copending application Serial No. 562,793, filed February 1, 1956.

The principal object of this invention is to provide a rivet and mandrelassembly for a riveting gun which handles a plurality of rivets, inwhich assembly a plurality of rivets is strung on a mandrel in seriesrelation and retained thereon so that the plurality can be easilyinserted into the gun.

Another object of the invention is to provide an article of commerce inthe form of a rivet and mandrel assembly including means forming apermanent part of the mandrel for holding a series of rivets on themandrel.

Other objects and advantages of the invention will be apparent from thefollowing description of a preferred embodiment, taken in connectionwith the accompanying drawings, in which:

Figure 1 is a plan view of a rivet and mandrel assemoly in accordancewith the present invention;

Figure '2 is a fragmentary plan view of the jaw end of a riveting toolshowing a rivet in position to have the head of the mandrel pulledtherethrough to expand the rivet;

Figure 3 is a sectional view through a rivet and plates to be fastenedthereby; and

Figure 4 is an enlarged sectional view similar to Fig. 3 showing therivet in place after having been expanded.

in certain types of blind riveting operations, it is customary to inserta rivet of the hollow type through a pair of sheet members to be rivetedtogether, and then expand the rivet by drawin an enlarged headtherethrough so that the blind end. of the rivet is expanded to securethe members together. In this type of operation it is extremelydesirable that the rivets be easily handled and be loaded easily intothe gun employed to install and expand the rivets.

in accordance with the present invention and cooperating with a rivetgun and adapted to be installed therein, there is provided a rivetassembly including a wire or mandrel 31 having a seriesof hollow rivets82 freely slidable thereon and having a rivet retaining shape forming apermanent part of the mandrel such as an integral upset portion 83 atone end thereof. At its other end the mandrel 81 has a head 86 joined tothe body of the mandrel by tapered or cam portion which is of adimension to retain the rivets 82 on the mandrel and increases towardthe head end of the mandrel so it can be pulled through the rivets onthe mandrel one at a time. The rivets 82 have their shank portionsdirected toward the cam portion of the head 86 of the mandrel 81 so thattheir heads are directed toward the rivet retaining portion 83. Sincethe rivet retaining portion 83 and head 86 of the mandrel are permanentparts of the mandrel, the mandrel 81 is not ordinarily reused and thematerial of such mandrel need be of substantially no greater durabilitythan that necessary to serve to expand the set of rivets 82 strung onthe mandrel.

Figure 2 shows the head or jaw end 87 of a riveting gun and in suchfigure the shank of a rivet has been inserted into aligned apertures intwo adjacent members 91 and 92 which are to be riveted together. Theriveting gun will not be further described and it will be understoodthat operation of such gun will pull the mandrel 81 to the right inFigure 2 so that the tapered cam portion of the head 86 of the rivetholding mandrel or wire 81 is drawn through the rivet and upsets orexpands the rivet. Referring to Figure 3, it will be noted that beforeexpanding the rivet 82 has two internal diameters, the larger diameterbeing of a size to cause the desired expansion within the members 91 and92. The smaller internal diameter of the rivet provides material at 82afor upsetting into overlapping relation with the member92. Figure 4shows an enlarged view of a rivet 82 when expanded or upset in theriveting operation.

While we have shown and described a preferred embodiment of theinvention, it will be apparent that the invention is capable ofvariation and modification from the form shown so that the scope thereofshould be limited only by the scope of the claims appended hereto.

We claim:

1. An article of commerce comprising a unitary as sembly of an elongatedmandrel and a plurality of hollow rivets, said mandrel having a bodyportion, an enlarged head at one end of said body portion, and a taperedrivet expanding cam portion rearwardly of said enlarged head and joiningsaid enlarged head to said body portion, a set of a plurality of hollowrivets strung on said body portion and each rivet having a shank portionwith a head at one end of said shank portion, said rivets being freelyslidable on said body portion and having their shank portions directedtoward said cam portion, said shank portions having an internal diameterless than the diameter of said enlarged head, said cam portion andenlarged head being capable of being pulled through each of saidplurality of rivets one after the other to expand the shank of saidrivets, said body portion having at its other end an enlarged rivetretaining portion, said enlarged rivet retaining portion being apermanent part of said mandrel and in conjunction with said enlargedhead holding said rivets on said mandrel until said rivet expandingportion and enlarged head is pulled through said rivets, the material ofsaid mandrel being of substantially no greater durability than thatnecessary to serve to expand the set of rivets strung on said mandrel.

2. The article of commerce defined in claim 1 in'which said enlargedrivet retaining portion is an integral part of said mandrel. 7

References Cited in the file of this patent UNITED STATES PATENTS1,800,459 Maclean Apr. 14, 1931 2,347,319 Hanset Apr. 25, 1944 2,650,722Stabile Sept. 1, 1953 2,706,039 Springate Apr. 12, 1955 FOREIGN PATENTS123,847 Australia Mar. 17, 1947

